火灾后钢材强度测定方法研究

发布时间：2018-04-13 05:24

  本文选题：火灾后 + 钢材强度　； 参考：《吉林建筑大学》2016年硕士论文

【摘要】：钢材自问世以来在建筑领域得到了广泛的应用,尤其是钢结构建筑如雨后春笋般在各大城市矗立起来。近年来钢结构建筑火灾事故频发,检测与修复工作尤为重要,火灾后的钢材强度是必须检测的性能指标。传统的截取试样的方法属于破损方法的一种,不利于后续的修复工作的开展。本文提出用非破损检测方法—里氏硬度法,来测定火灾后钢材的强度,建立了火灾后钢材强度与里氏硬度的关系曲线及计算公式。首先,本课题选取了钢结构中常用的型材H型钢作为试验对象,在承担70%设计压力下经历火灾高温过程。火灾试验设置了6种不同的温度,分别是100℃~600℃,并对恒定温度下的加热时间做出了限制,用了两种冷却方式模拟消防灭火,分别是浇水冷却方式和自然冷却方式。高温冷却后的试件,按承担70%的火灾后剩余承载力的受力状态和用机械式千斤顶固定的非受力状态两种情况,测试试件的里氏硬度值。在同一试件上,按翼缘位置的上中下检测部位和腹板位置的上中下检测部位分别测试里氏硬度值。在每个试件的翼缘和腹板分别截取标准试样,用拉力试验机测试其力学性能,并记录数据。最后,对于冷却方式、温度、受力状态、检测部位等因素对里氏硬度测试值的影响进行了分析,并采用线性和非线性两种方法对试验数据进行了回归分析,综合考虑所有影响因素拟合出了试件翼缘位置和腹板位置的里氏硬度与抗拉强度的曲线,确定了两个位置的回归方程,为火灾后钢材强度的检测提供了依据。
[Abstract]:Steel has been widely used in the field of architecture since it came out, especially the steel structure building sprang up in every big city.In recent years, steel structure fire accidents occur frequently, detection and repair work is particularly important, the strength of steel after the fire is the performance index that must be tested.The traditional method of sample interception belongs to the method of breakage, which is not conducive to the development of subsequent restoration work.In this paper, a non-breakage testing method, the Richter hardness method, is proposed to measure the strength of steel after fire. The relationship curve and calculation formula between the strength of steel after fire and Riemann hardness are established.Firstly, H-section, which is commonly used in steel structure, is selected as the test object, and it experiences fire high temperature process under 70% design pressure.Six different temperatures were set up in the fire test, which were 100 鈩，

本文编号：1743114